A morphological assessment of vein allografts preserved in glycerol and used for arterial replacement.

There is an increasing need for alternatives to reversed autogenous saphenous vein in the treatment of first-time and recurrent arterial occlusions. Vein grafts taken from rats and goats and from humans were preserved in glycerol, reconstituted in saline and compared morphologically with fresh veins of similar origin. In rats and goats, autograft, allograft and glycerol-preserved allograft veins were used to replace lengths of common iliac and carotid arteries. After various periods of time these were retrieved and examined using light microscopy and scanning electron microscopy. Appearances were found to correlate well with function. All allograft vessels were found to have failed. Over 70% of autografts were functional in both species and all of these had re-endothelialised. In rats, all of the glycerol-preserved grafts had failed but in goats 64% were patent at 6 months but did not show signs of a neointima. In larger animals, glycerol-preserved vein allografts appear to offer an acceptable form of arterial replacement where fresh vein autograft is unavailable.